Method, apparatus, and program product for securely presenting situation information

ABSTRACT

We present technology that allows layman computer users to simply create, provision, and maintain secured infrastructure—an instant PKI. This technology can be used in a wide variety of applications including wired and wireless networks, secure sensor networks (such as medical networks), emergency alert networks, as well as simply and automatically provisioning network devices whether secure or not.

RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Patent Application60/480,909 filed Jun. 24, 2003, entitled “Method And Apparatus ForEstablishing And Using A Secure Credential Infrastructure” withinventors Smetters, Balfanz, Durfee, Grinter, Stewart, Hao-and Wonghereby incorporated by reference in its entirety herein.

This application is related to:

U.S. patent application Ser. No. 10/656,494 entitled “Method, Apparatus,and Program Product for Automatically Provisioning Secure NetworkElements” filed concurrently herewith, with the same inventors.

U.S. patent application Ser. No. 60/480,909 entitled “Method andApparatus for Establishing and Using a Secure Credential Infrastructure”filed concurrently herewith, with the same inventors.

U.S. patent application Ser. No. 10/656,551 entitled “Method, Apparatus,and Program Product for Provisioning Secure Wireless Sensors” filedconcurrently herewith, with the same inventors.

U.S. patent application Ser. No. 10/066,699 entitled “Systems AndMethods For Authenticating Communications In A Network Medium” filedFeb. 6, 2002 with inventors Balfanz, Lopes, Smetters, Stewart, and Wong.

BACKGROUND

1. Field

Embodiments of this invention relate to the field of cryptography.

2. Background

Adoption of public key cryptography has been tremendously limited by the“key management problem” that is, the problem of allowing users toreliably identify the public keys of their intended communicationpartners. One approach used to address this problem is to construct aPublic Key Infrastructure (PKI). This approach designates one or moretrusted public keys known by the members of the PKI. The computer systemthat has the trusted public keys can sign digital certificatescontaining the public keys of users and devices in the PKI. This processauthenticates the public keys of the PKI members.

The primary difficulty addressed by PKI is the problem of key managementand distribution. That is, of deciding how to get authenticated copiesof particular individuals' or devices' public keys to those individualsand devices that need to rely on these keys. A PKI is a system ofwell-known trusted public keys, possibly hierarchically organized. InPKI the owner of a trusted key is usually termed a “CertificationAuthority”, or CA. Those trusted keys are used to authenticate the keysof other members (users and devices) in the PKI by signing the keys forthe members, thus creating a “digital certificate”. Such a certificatetypically uses this trusted signature to link a public key toinformation indicating who owns the key (an identity certificate), orwhat the key is allowed to be used for (an attribute certificate), or atvery minimum, just that the bearer of the corresponding private key is avalid member of this particular PKI or other trust system.

Such a PKI simplifies the key management problem, as the number of keysthat must be exchanged a priori goes from many down to the number of thetrusted public keys. As long as the information contained in a member'scertificate is sufficient to indicate to the verifier of thatcertificate that they are communicating with their intended party, thesignature on that certificate is enough to let them know that the publickey contained therein belongs to a trusted entity.

Unfortunately, creation and management of PKIs, as well as distributionof certificates, has turned out to be incredibly difficult and complex.Even establishment of small special-purpose PKIs to support the use ofpublic key cryptography for one application within one organization isgenerally considered to be too expensive and difficult. One reason forthis is that the available software is complicated, expensive, andrequires deep knowledge of standards and cryptography to be configuredto be effective. As a result, in spite of the fact that the use ofpublic key cryptography can dramatically increase the security of manycommunications protocols (as compared, for example, to password-basedalternatives), protocol designers are forced to move to less securealternatives that do not require the “burden” of PKI establishment.Similarly, this cost of setting up a PKI keeps individuals fromconsidering larger-scale use of public key cryptography in embeddeddevices (e.g. cell phones, printers, etc), as each of these deviceswould have to be “provisioned” with a certificate before use.

Furthermore, the key management and distribution problem described abovein the PKI context exists with any secure credential infrastructure thathas a credential issuing authority to issue credentials.

A derivative problem exists for wireless networks. These networks haveproved notoriously difficult for even knowledgeable corporate ITdepartments to configure securely. This has led to many deployednetworks exposing information and network resources to strangers thus,leaving client machines vulnerable to attack. While standards bodieshave begun to specify technologies capable of securing these networks,these new security technologies are complex, and even more difficult toconfigure and manage than the existing technologies. In manyenvironments (for example home or small business wireless networks), itwill be difficult, if not impossible, for network users to effectivelyconfigure and manage these networks to make them secure (many currentwireless users find that 802.11b WEP is difficult to configure).

The standards body responsible for improving the security of the 802.11standard are adapting the 802.1x standard for use on 802.11 networks.

In 802.1 X's most secure configuration, clients and authenticationservers authenticate each other and secure their communications usingTransport Layer Security (TLS), which requires both the client andserver to have a digital certificate with which they authenticate toeach other. To distribute such certificates requires the deployment of aPKI (or other secure credential infrastructure) and the installation ofa unique client certificate on each network client. This is anotoriously difficult task and subject to incorrect configurations thatcan leave clients vulnerable to rogue machines who can gain access tothe shared wireless medium; those rogue machines can then use thosevulnerable (but authenticated) clients as a base from which to attackthe corporate LAN. Again, in situations where this approach issuccessful, it is either difficult to configure and manage, expensive,or totally out of the reach of small network users.

Similar problems also exist for simple wired networks. For example, ifproviding static IP addresses or adding a computer to a domain,currently an employee often must have their computer configured by an ITprofessional responsible for maintaining the addresses.

Another problem exists in the medical field. Security for patient datain the hospital setting has always been important, but with the adventof new HIPAA guidelines, it has become legally mandatory. At the sametime, sensors or devices that gather patient data must be highly usableby a community of doctors and nurses who may not be experts in computertechnology.

Today, nurses' assistants manually measure and record temperature andblood pressure. These measurements are available through a physicalchart, providing no ability for graphing of data over time, etc. Thereare some facilities for automatic monitoring of patients (e.g. EKGmachines), which can be connected to alarm facilities at nursesstations, but these facilities are expensive, and don't allow theintegration of arbitrary sensors, and they all require the use ofcables, wires or tubes between the sensor and the patients. Thesecables, wires and tubes cause significant room clutter and are a tripand snag danger to the patient and the medical staff.

Some companies are beginning to commoditize the automation of patientmonitoring by attaching wireless sensors to patients The patent data canbe transmitted over an 802.11, other wireless, or wired network to apatient database. Such a system, however, requires securing of the linksbetween the sensors and the patient database. This security must notonly prevent eavesdropping by arbitrary attackers, but in order tocomply with HIPAA, must enforce access control between legitimatemembers of the hospital community. There are no good solutions on themarket for this problem, and traditional approaches, such as passwords,do not translate well to embedded devices such as sensors.

In yet another situation, patients using sensors at home face similarproblems with securing data transmission to their doctors (or evenconfiguring the monitoring devices to appropriately communicate data totheir doctors). Some sensor devices use phone-based data transmission tohandle both getting the data to the right place, and limiting access tothe data in transit. However, the use of wireless sensors and the use ofthe internet or cellular phone networks to transmit such data isexpected to increase as will the need to keep the data secure.

Turning to yet another problem, today, Emergency Operations Centers(EOC) communicate with the public largely using broadcast and telephonymedia. During an emergency EOC can use computer assisted dedicatedswitching systems to program specific messages for either the entirecitizenry or a subset of those people who can be reached (for example,by specifying a location, type of building, or area of affect). Thecomputer system in turn generates an automatic message that is playedwhen a telephone is answered. The computer system then initiates callsto the targeted citizenry. The EOC can also communicate with the publicby requesting that television and radio stations broadcast informationalannouncements. EOC commanders recognize that neither approach reachesall members of the public. In addition, the telephone calling system iseasy for criminals to abuse.

It would be advantageous to provide a simpler way to create a securecredential infrastructure such as a PKI. It would also be advantageousto simplify the configuration (including the security aspects) ofwireless access points (WAP) as well as simplifying the process ofconfiguring a network even for wired networks. Furthermore, it would beadvantageous to simplify the provisioning of sensors that provide datathat needs to be secure. It would be still further advantageous toprovide a secure means for providing public service notices.

DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a networked computer system in accordance with oneembodiment;

FIG. 2 illustrates a secure credential infrastructure constructionprocess in accordance with one embodiment;

FIG. 3 illustrates a credential issuing authority configuration processin accordance with one embodiment;

FIG. 4 illustrates a process that can be used by a credential issuingdevice to pre-authenticate a prospective member device over a preferredchannel in accordance with one embodiment;

FIG. 5 illustrates a process that can be used by a prospective memberdevice to pre-authenticate a credential issuing device over a preferredchannel in accordance with one embodiment;

FIG. 6 illustrates an automatic prospective member device credentialprovisioning process in accordance with one embodiment;

FIG. 7 illustrates one embodiment of the prospective member deviceprovisioning process;

FIG. 8 illustrates one embodiment of a wireless access point securecredential infrastructure system;

FIG. 9 illustrates an enrollment station based configuration system inaccordance with one embodiment;

FIG. 10 illustrates an automatic network device configuration process inaccordance with one embodiment;

FIG. 11 illustrates a secure wireless sensor system deployed in amedical setting in accordance with one embodiment; and

FIG. 12 illustrates one embodiment of a secure community alert system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

One aspect of the embodiments disclosed herein is technology forcreating a simple-to-use secure credential infrastructure. Such aninfrastructure could be, for example, an “Instant PKI”. That is, a PKIthat is simple to establish, configure and use without diminishing thesecurity provided by the PKI.

Another aspect is technology for automatically provisioning devicesusing a location-limited channel and of using this technology inexemplary systems such as for medical sensors and household alarms.

Still another aspect of the disclosed embodiments includes easilyprovisioned sensors that can securely send sensor data to a destination.Such sensors can be used in a wide variety of applications.

Yet another aspect of the disclosed embodiments includes securesituation notification devices that can be used to securely receive andpresent information directed to a specific receiver.

FIG. 1 illustrates a networked computer system 100 that incorporates oneembodiment of the invention. The networked computer system 100 includesa computer 101 that incorporates a CPU 103, a memory 105, and a networkinterface 107. The network interface 107 provides the computer 101 withaccess to a network 109 over a network connection 108. The computer 101also includes an I/O interface 111 that can be connected to a userinterface device(s) 113, a storage system 115, and a removable-mediadata device 117. The removable-media data device 117 can read a computerreadable media 119 that typically contains a program product 121. Thestorage system 115 (along with the removable-media data device 117) andthe computer readable media 119 comprise a file storage mechanism. Theprogram product 121 on the computer readable media 119 is generally readinto the memory 105 as a program 123. In addition, the program product121, or updates to same, can be provided from the network as computerinstruction signals embodied in a transmission medium (with or without acarrier wave upon which the signals are modulated or other datatransporting technology—including light, radio, and electronicsignaling) through the network interface 107. One skilled in the artwill understand that a device in communication with the computer 101 canalso be connected to the network 109 through the network interface 107using the computer 101.

A member device 125 can also communicate over the network 109 over anetwork connection 127. The member device 125 can also communicate withthe computer 101 over a preferred channel 129 through the networkinterface 107 or the I/O interface 111 (not shown).

One skilled in the art will understand that not all of the displayedfeatures of the networked computer system 100 nor the computer 101 needto be present for all embodiments of the invention. Further, such a onewill understand that the networked computer system 100 can be anetworked appliance or device and need not include a general-purposecomputer. The network connection 127, the network connection 108, andthe preferred channel 129 can include both wired and wirelesscommunication. In addition, such a one will understand that the userinterface device(s) 113 can be virtual devices that instead ofinterfacing to the I/O interface 111, interface across the networkinterface 107.

Further, one skilled in the art will understand that a procedure can bea self-consistent sequence of computerized steps that lead to a desiredresult. These steps can be defined by one or more computer instructions.These steps can be performed by a computer executing the instructionsthat define the steps. Thus, the term “procedure” can refer (forexample, but without limitation) to a sequence of instructions, asequence of instructions organized within a programmed-procedure orprogrammed-function, or a sequence of instructions organized withinprogrammed-processes executing in one or more computers. Such aprocedure can also be implemented directly in circuitry that performsthe steps. Further, computer-controlled methods can be performed by acomputer executing an appropriate program(s), by special purposehardware designed to perform the steps of the method, or any combinationthereof.

One embodiment is directed to the construction of a secure credentialinfrastructure. Such secure credential infrastructures include wired andwireless networks that use keys (for example, secret keys, orpublic-private key pairs) to encrypt information sent over a networksuch that the data representing the encrypted information only carriesmeaning to those computers that have the correct key, or a credentialinfrastructure that allows devices to use credentials to authenticate toother members, or to use credentials to authenticate to other members orservice providers (for example, logging onto a Windows domain using asmart card that has a credential stored within it). This embodimentapplies to secure credential infrastructures such as a public keyinfrastructure, to wireless networks (for example those using WEPencryption, or other wireless encryption standard), to wired networks,and to hybrid networks. One embodiment of the invention can be used toadd target devices to a public key infrastructure (PKI) and thus,construct a PKI having member devices. Although much of the following isdirected towards a secure credential infrastructure, one skilled in theart will understand that the inventive aspects apply as well to a PKI.

FIG. 2 illustrates a ‘secure credential infrastructure construction’process 200 that is invoked when power is first applied to a credentialissuing device, or when the credential issuing device is reset. The‘secure credential infrastructure construction’ process 200 initiates ata ‘start’ terminal 201 and continues to a ‘credential issuing authorityconfiguration’ procedure 203 that configures a credential issuingauthority (for example a certification authority for a PKI) as issubsequently described with respect to FIG. 3.

Once the certification authority is configured, the ‘secure credentialinfrastructure construction’ process 200 continues to a ‘prospectivemember device pre-authentication’ procedure 205 that detects when aprospective member device is available to communicate to the credentialissuing device over a preferred channel, optionally provides networkconfiguration information to the prospective member device to enable itto communicate with the credential issuing device over some networkother than the preferred channel, and pre-authenticates the prospectivemember device. The ‘prospective member device pre-authentication’procedure 205 is subsequently described with respect to FIG. 4.

Once the prospective member device is pre-authenticated, an‘automatically provision prospective member device with credential’procedure 207 provisions the prospective member device by providing theprospective member device with a credential (in the PKI case, a publickey certificate) for the prospective member device as well as thecredential issuing device's public key certificate and any otherinformation that is requested by the prospective member device, orautomatically provided by the or enrollment station. Once provisioned,the prospective member device becomes a member device of the securecredential infrastructure. The ‘automatically provision prospectivemember device with credential’ procedure 207 is subsequently describedwith respect to FIG. 6.

The ‘secure credential infrastructure construction’ process 200 repeatsback to the ‘prospective member device pre-authentication’ procedure 205for each prospective member device to be added to the secure credentialinfrastructure.

A credential can include a X.509 certificate, a WTLS certificate, a SPKIcertificate, an attribute certificate, or any other association of a keyor secret with trust, access, or identity.

Once the prospective member device is provisioned it becomes a memberdevice and can use its credential as is known in the art. This includesusing the credential to enable secure communications across a network,to use credential to provide access to devices, networks, services,containers, office space, or other device, area, or service thatrequires authentication and/or authorization or a credential to access.

Any device that performs the ‘secure credential infrastructureconstruction’ process 200 as well as any device that performsprovisioning services for other secure networks is contemplated as acredential issuing device. Often, the credential issuing device includesa credential issuing authority (in the context of a PKI, a certificationauthority (CA)). One skilled in the art will understand that a publickey infrastructure is but one instance of a secure credentialinfrastructure that includes a credential issuing authority (such as acertification authority) that provides a credential (such as a publickey certificate) through a credential issuing device to the prospectivemember device. Possession of the credential by the prospective memberdevice makes the device a member device of the secure credentialinfrastructure. Possession of the credential provides the member devicewith the ability to authenticate and/or authorize, or to access.

The preferred channel can be a location-limited channel or any otherchannel that has both a demonstrative identification property and anauthenticity property.

The demonstrative identification property requires that identificationbe based on a physical context (for example but without limitation, “theprinter in front of me,” “all PDA's in the room,” or “this device that Iam touching”). The preferred channel uses communication technologiesthat have inherent physical limitations on their transmissions. Examples(but without limitation) of such technologies include visible orinvisible electromagnetic radiation communication such as infraredcommunications, communications through a short run of wires, audio (bothaudible, and inaudible (for example ultrasonic)), communication bypassing information from one device to another device using a physicalcomputer-readable media (such as a removable media or drive (forexample, a floppy disk, a removable disk, a USB storage device (such asa flash memory pen or disk drive) or other tangible data carrier)),physical electrical contact, near-field signaling across the body, andshort range RF, as well as embodiments that require an operator to entera code (other examples can be found in the discussion with respect toFIG. 8). The demonstrative identification property of the preferredchannel means that human operators are aware of which devices arecommunicating with each other over the preferred channel and that thehuman operators can easily detect when an attack is being made on thepreferred channel.

The authenticity property of the preferred channel means that it isimpossible or difficult for an attacker to transmit over the preferredchannel or tamper with messages sent over the preferred channel withoutdetection by the legitimate parties to the communication.

The preferred channel does not require secrecy (that is, an attacker canmonitor the transmissions on the preferred channel) so long as theattacker cannot transmit on the preferred channel without detection.Because of the location-limited nature of the preferred channel, it isdifficult for an attacker to monitor the channel, let alone transmit onthe channel without detection. Further, detection only requires that thehuman participants know the number of the participants (devices) who arecommunicating over the preferred channel.

As is subsequently described, the use of the preferred channel topre-authenticate the participants' keys allows the administrator of thesecure credential infrastructure to be assured that the keys are onlyprovided to prospective member devices that have access to the preferredchannel. Thus, establishing “trust” because the user of the prospectivemember device must have had physical access to the preferred channel(for example, when the user is an employee and has had access to thebuilding where the preferred channel is located).

During the pre-authentication process, commitments (commitments aresubsequently described) to each participant's public keys are exchangedover the preferred channel. Once the commitments are exchanged, thedevices can perform a key exchange protocol or procedure and establishfurther secure communication using any method known in the art. Toillustrate, once a key is received, it is verified by checking that thereceived key matches the commitment that was provided via the preferredchannel. Once the keys are verified, well-known techniques can be usedto commence communication using the keys (and in addition, in the caseof a public key, also verifying that the other device holds the privatekey corresponding to the provided public key). Once the public keys areverified and the provider of the public key proves possession of theprivate key that corresponds to the public key, the credential issuingauthority can provide a credential to the prospective member device forits use such that the prospective member device becomes an actual memberdevice of the PKI.

A commitment to a piece of information X is a piece of information Cthat can be verified to match X. A commitment is “binding,” when it iscryptographically difficult for an attacker, even knowing X and C, toproduce a different piece of information Y that C will also match.

A commitment is “hiding” when it cryptographically difficult for anattacker knowing C to extract even partial information about X.

An example of a binding and hiding commitment to X can be H(X) where Hcan be a cryptographically secure hash function. One skilled in the artwill understand from the context whether the commitment used needs to bebinding, hiding, or both.

A commitment can be used to establish trust if it is received over apreferred channel or endowed with a digital signature from a party therecipient trusts. A trusted commitment allows the level of trust of amatching piece of information (possibly received over an untrustedchannel, or unsigned) to be elevated to the same level of trust as thecommitment.

FIG. 3 illustrates a ‘credential issuing authority configuration’process 300 that can be used by the ‘credential issuing authorityconfiguration’ procedure 203 of FIG. 2. This process can be used toinitialize the credential issuing device so that it has a trustedcredential. The ‘credential issuing authority configuration’ process 300initiates at a ‘start’ terminal 301 and continues to a ‘create trustedkey pair’ procedure 303 that generates public and private keys usingwell-known techniques. Once the trusted key pair is generated, a ‘storetrusted key pair’ procedure 305 stores the trusted key pair on a storagedevice (for example, but without limitation, a disk, a cryptographictoken, network device, network storage, memory card, etc.). Once thetrusted key pair is generated, the ‘credential issuing authorityconfiguration’ process 300 continues to a ‘create issuing authoritycredential’ procedure 307. One skilled in the art will understand thatthere are other types of credential systems other than certificationsystems that can be provisioned as described herein.

The ‘create issuing authority credential’ procedure 307 can create aself-signed credential (a “root” credential). The ‘create issuingauthority credential’ procedure 307 can also access a parentcertification authority to obtain a chained credential and to import thechained credential back to the credential issuing device. Once thecredential is created or obtained, a ‘store issuing authoritycredential’ procedure 309 stores the credential in some availablestorage for subsequent use.

Other services or features can be initialized by an ‘otherinitialization’ procedure 311. These services and/or features caninclude directory services, generation of certificate revocation lists(CRLs) or credential status processing as well as other services. Inaddition, these services can include, for example, key-pair generationservices, 802.11a/b/g provisioning services, network addressprovisioning services etc. The ‘credential issuing authorityconfiguration’ process 300 completes through an ‘end’ terminal 313.

FIG. 4 illustrates a pre-authentication process for a credential issuingdevice 400 that can be used by the ‘prospective member devicepre-authentication’ procedure 205 of FIG. 2.

The pre-authentication process for a credential issuing device 400 canbe used to establish trust between the credential issuing device and theprospective member device such that the prospective member device can beprovisioned with a credential and become a member device of the securecredential infrastructure.

The pre-authentication process for a credential issuing device 400initiates at a ‘start’ terminal 401 and continues to an ‘initializelocation-limited ports’ procedure 403 that activates one or more I/Oports of the credential issuing device that will be used to establish apreferred channel with the prospective member device.

A preferred channel can be established using any location-limitedcommunication mechanism such as those described with respect to FIG. 8.Once the preferred channel ports are initialized, the pre-authenticationprocess for a credential issuing device 400 continues to an ‘establishcommunication over preferred channel’ procedure 405 that establishescommunication over the preferred channel between the credential issuingdevice and the prospective member device using one of the locationlimited ports initialized by the ‘initialize location-limited ports’procedure 403. Once communication is established between the prospectivemember device and the credential issuing device (for example by aligningIR ports on the devices), the pre-authentication process for acredential issuing device 400 continues to an ‘exchange commitmentinformation’ procedure 407 that generates a commitment for the publickey. The commitment will be sent to the prospective member device overthe preferred channel. The commitment can be a portion of the publickey, the public key itself, an encoding of the public key, amathematical function of the public key or other function of the keygenerated by any commitment technique. The credential issuing devicealso receives a commitment from the prospective member device for thekey or secret that the prospective member device will send to thecredential issuing device.

Next a ‘provide communication enablement information’ procedure 409 canprovide the prospective member device with network configurationinformation required for the credential issuing device to communicate tothe prospective member device over the desired communication media (ascompared to the preferred channel). For example, where the credentialissuing device is a WAP, it could specify the SSID and possibly awireless channel selection and/or a WEP key; for a wired network, thecredential issuing device could specify a specific MAC address and/orstatic IP address. One skilled in the art will understand that the‘provide communication enablement information’ procedure 409 is optionalin many embodiments and that the prospective member device can bepre-configured for network communication. However, one advantage of the‘provide communication enablement information’ procedure 409 is that itsimplifies the network configuration process for the prospective memberdevice. For example, but without limitation, the credential issuingdevice can automatically assign a fixed network address to theprospective member device (as compared to a DHCP address), specify aSSID, specify a WEP key, a domain name, an IP address, a VPN address,gateway address, Bluetooth address, security settings, securitypolicies, bit lengths, or other information needed to establishcommunication between the credential issuing device and the prospectivemember device over a channel other than the preferred channel. Inaddition, other information can be provided beyond just networkconfiguration information. Furthermore, the communication enablementinformation can be used to bootstrap a secure communication channel thatcan be used to further provision the prospective member device, forexample as is subsequently described with respect to FIG. 6. Inaddition, similar information can be provided during subsequentprovisioning using a secure channel.

Once the commitments are exchanged, an ‘key exchange’ procedure 411exchanges keys (for example using any key-exchange protocol known in theart) such that the credential issuing device and the prospective memberdevice will be able to perform communication over a network that is notthe preferred channel. The ‘key exchange’ procedure 411 need not use thepreferred channel or an encrypted data path to exchange public keys.However, if secret keys are being exchanged secure communication arerequired (such as using the committed-to keys to establish securecommunication over a non-preferred network; and using the establishedsecure communication channel to negotiate exchange of a secret key).Furthermore, the preferred channel can be used with the ‘key exchange’procedure 411 so long as any secret data is encrypted (and preferablyusing a protocol such as SSL). This can be useful where the preferredchannel has sufficient bandwidth to timely carry the protocol.

Once the keys are exchanged, a ‘verify keys with commitment’ procedure413 verifies that the received key matches the commitment (this can bedone both by the credential issuing device and the prospective memberdevice with the commitments and keys they have received respectively).For example, verifying that a received key matches a commitment can beperformed by computing a cryptographic hash of the key and verifyingthat this hash is equal to the commitment. Once the public keys areverified by the commitment information, a ‘verify possession of privatekey’ procedure 414 establishes proof that the device providing theverified public key also has possession of the corresponding private key(for example using a key-pair validation mechanism that uses techniqueswell known in the art). Finally, the pre-authentication process for acredential issuing device 400 completes through an ‘end’ terminal 415.

In one embodiment of the invention, the actual key can be provided asthe commitment. Then when keys are exchanged, verifying that thereceived key matches the previously received commitment can be donesimply by verifying that they are equal.

FIG. 5 illustrates a pre-authentication process for a prospective memberdevice 500 that is very similar to the pre-authentication process for acredential issuing device 400 of FIG. 4. The pre-authentication processfor a prospective member device 500 includes a ‘start’ terminal 501, an‘initialize location-limited ports’ procedure 503, an ‘establishcommunication over a preferred channel’ procedure 505, an ‘exchangecommitment information’ procedure 507, a ‘receive communicationenablement information’ procedure 509, an ‘key exchange’ procedure 511,a ‘verify keys with commitment’ procedure 513, a ‘verify possession ofprivate key’ procedure 514, and an ‘end’ terminal 515. These proceduresare substantially the same as the corresponding procedure shown in FIG.4 with the exception of the ‘receive communication enablementinformation’ procedure 509.

The ‘receive communication enablement information’ procedure 509receives the information provided by the credential issuing device atthe ‘provide communication enablement information’ procedure 409 andconditions the prospective member device so that it can communicate overone or more networks, or otherwise processes the communicationenablement-specific information as appropriate.

With regards to the ‘establish communication over preferred channel’procedure 405 and the ‘establish communication over a preferred channel’procedure 505, there are at least two modes for establishingcommunication over the preferred channel. These modes differ in how thecommunication is established. In a first mode, the prospective memberdevice can explicitly initiate the connection to the credential issuingdevice over the preferred channel and request a credential (either aspart of an initial auto-configuration of the client, in request tostimuli from the environment—for example, detection of a new wirelessnetwork—, as a result of input from the user, or by an automateddiscovery process). This can be accomplished by having the prospectivemember device initiate the exchange of credentials with the designatedthe credential issuing device. One example of establishing a preferredchannel is by aligning infrared or visible light ports of theprospective member device and the credential issuing device. Additionalexamples of connection examples are subsequently described with respectto FIG. 8.

Designation of the credential issuing device can be explicit (forexample, “this device to which I have established an electricalconnection”, “this device I touch,” “this device that is aligned with aspecific IR port,”) or implicit (for example, “any device that canreceive audible signals issued from my device”).

In the second mode, the communication over the preferred channel can beinitiated by the credential issuing device in response to an action suchas a user placing the prospective member device in a cradle attached tothe credential issuing device by a serial port, or USB port or by havingthe prospective member device respond to a credential-granting tokenassociated with the secure credential infrastructure. Using thisapproach, the prospective member device generally can be configured tobe able to accept the pre-authentication requests from the credentialissuing device. The prospective member device in this configuration, forexample, can be executing an application that receives credentials anddetermines and processes the received credentials. In another example,the prospective member device can support a background program (forexample, a UNIX daemon) that receives the credential and makes itavailable to other registered applications (with optional userconfirmation or other feedback). Note that the cradle should not be awireless cradle (that is, a cradle that wirelessly sends information tothe credential issuing device) unless the communication between thecradle and the credential issuing device is secure.

A credential-granting token can include portable credential issuingdevices (like a JAVA card), smart cards that can create credentials anddirectly provision prospective member devices. Other devices can, forexample, serve as storage devices for accumulating and storingcommitments between a group of prospective member devices that are tobelong to a secure credential infrastructure. Finally, the credentialissuing device can require identification of a key to enable thecredential issuing function of the credential issuing device (forexample, such a key can be a USB storage or biometric sensor that mustbe accessed prior to the credential issuing device provisioning acredential).

One skilled in the art will understand that the commitment to the key istransferred over the preferred channel because the preferred channel isassumed to be resistant to undetected active attacks and to therebyendow data transferred across it with the authenticity property. Achannel does not need to be resistant to eavesdroppers to be used as apreferred channel because only public information (e.g. a public key, ora commitment to a public key) is sent over that channel; a pair ofdevices authenticating themselves to each other by sending such key orcommitment information over the preferred channel are able to set up asecure communication with each other because they can demonstratepossession of the private keys corresponding to the public keyscommitted to or exchanged over the preferred channel (using anytechnique known in the art, such as a key exchange protocol likeSSL/TLS). An eavesdropper that detects the commitment or keys sentacross the preferred channel is not able to demonstrate possession ofthe corresponding private key, and therefore is unable to affectcommunication between the legitimate parties. Further, one skilled inthe art will understand that the preferred channel can be a very lowbandwidth channel as only needs to carry the key commitment (andpossibly essential communication parameters for the non-preferredchannel—such as a LAN, or Internet). The provisioning of the credentialand other information to the prospective member device can beaccomplished using the non-preferred channel(s).

Example protocols for exchanging commitments follow:

Pre-authentication for two keys, taking place over the preferredchannel:

-   -   1. A→B: addr_(A), h(PK_(A))    -   2. B→A: addr_(B), h(PK_(B))        Authentication continues over a non-preferred (wireless) channel        with any standard key exchange protocol to exchange PK_(A) and        PK_(B) to establish secure communications, e.g.:    -   1. A→B: TLS CLIENT HELLO    -   2. . . . and so on.        The various symbols denote:    -   addr_(A), addr_(B): A's (resp. B's) address in wireless space,        provided strictly for convenience;    -   PK_(A), PK_(B): the public key belonging to A (resp. B), either        a long-lived key or an ephemeral key used only in this exchange;    -   h(PK_(A)): a commitment to PK_(A), e.g., a one-way hash of an        encoding of the key.

Pre-authentication for one key, taking place over the preferred channel:

-   -   1. A→B: addr_(A), h(PK_(A))    -   2. B→A: addr_(B), h(S_(B))        Authentication continues over a non-preferred (wireless) channel        with any standard key exchange protocol to exchange PKA and a        secret, e.g.:    -   1. A→B: PK_(A)    -   2. B→A: E_(PKA)(S_(B))        The various symbols denote:    -   addr_(A), addr_(B): A's (resp. B's) address in wireless space,        provided strictly for convenience;    -   PK_(A): the public key belonging to A either a long-lived key or        an ephemeral key used only in this exchange;    -   S_(B): a secret belonging to B;    -   h(PK_(A)): a commitment to PK_(A), e.g., a one-way hash of an        encoding of the key;    -   h(S_(B)): a commitment to S_(B)    -   E_(PKA)(S_(B)): the encryption of S_(B) Under PK_(A)

FIG. 6 illustrates an automatic prospective member device credentialprovisioning process 600 that can be used by the ‘automaticallyprovision prospective member device with credential’ procedure 207 ofFIG. 2. The automatic prospective member device credential provisioningprocess 600 provisions the prospective member device with thecredential. It also sends the prospective member device otherprovisioning information (for example, information requested by theprospective member device or that is automatically provided by thecredential issuing device.

The automatic prospective member device credential provisioning process600 initiates at a ‘start’ terminal 601 and continues to an ‘acquireprovisioning information request’ procedure 603. The ‘acquireprovisioning information request’ procedure 603 can receive a requestfor provisioning information from the prospective member device. Inaddition, the ‘acquire provisioning information request’ procedure 603can detect a condition that triggers the credential issuing device toprovide pre-determined or user selected provisioning information. Therequest can include requests for information or services beyond that ofjust providing a credential.

Once the credential issuing device acquires the request, a ‘generateprovisioning information’ procedure 605 generates a credential (such asone or more public key certificates) and any other requestedprovisioning information. The ‘generate provisioning information’procedure 605 can include requesting authorization for the credentialfrom a registration agent (for example from an RA in a PKI).

A ‘send credential’ procedure 607 causes the credential issuing deviceto send one or more credentials to the prospective member device. Oncethe prospective member device receives the credential, it becomes amember device of the secure credential infrastructure. Also, a ‘sendprovisioning information’ procedure 609 sends the provisioninginformation from the credential issuing device to the prospective memberdevice.

The prospective member device can also request that it be provisionedwith a key-pair generated by a credential issuing device or any otherinformation that may be available. One skilled in the art willunderstand that some embodiments can send provisioning information thatis not requested by the prospective member device (for example,application specific information).

Furthermore, the prospective member device can be provisioned withinformation that can be used by the prospective member device toestablish a Virtual Private Network (VPN) with some other member device,security gateway, etc.

One skilled in the art will understand that the ‘automatically provisionprospective member device with credential’ procedure 207 in someembodiments will only provision the prospective member device with thecredential, while other embodiments will provision the prospectivemember device with both the credential and other requested (or default)provisioning information (and in some embodiments may not provision acredential at all—see FIG. 10 and its discussion).

The provisioning information can be any information that can be used bythe prospective member device. This information can include applicationspecific information, site specific information, network specificinformation, or other information. This information can also include,for example but without limitation, information such asapplication-dependent information, device-specific assignmentinformation (for example, in a hospital environment, the name of thepatient, the case number, or other data-acquisition information requiredto capture data from the device or to cause the device to operate),database access information, cell phone provisioning information (suchas the cell phone number), any kind of owner information, vehicleinformation, location information, information required to establish asecure communication link (for example VPN-related information),collaborative work space information, radio channel, any kind ofapplication specific information, and information required to access adatabase. Thus, the term “provisioning” applies to the providing of acredential, as well as the providing of other information that can beused by a member device. In some embodiments, the provisioninginformation can be provided using multiple communication channels. Inparticular, the preferred channel can be used to send provisioninginformation to bootstrap subsequent communication (secure or notsecured) over the preferred or non-preferred channel (for example,information necessary to establish temporary communication over anon-preferred channel). The two parties can then go on to exchangeadditional provisioning information over that non-preferred channelsubsequent to the ‘key exchange procedure’ and ‘key verificationprocedure’ described above, which can be used to establish secure andauthenticated communication between the parties over that non-preferredchannel. This additional provisioning information can contain any of theprovisioning information types described above, including communicationenablement information sufficient to allow the new member device tocommunicate on another non-preferred network connection not used duringthe provisioning. In other embodiments, the preferred channel can beexclusively used to provision the prospective member device, possiblywith the use of a key exchange protocol to additionally secure some ofthat communication. The more common embodiment will be where a first setof provisioning information is provided over the preferred channel, andother provisioning information is provided using a second (generallysecure) communication channel.

FIG. 7 illustrates a ‘prospective member device-side provisioning’process 700 that can be used by the prospective member device toautomatically receive a credential and other provisioning informationfrom the credential issuing device. The ‘prospective member device-sideprovisioning’ process 700 initiates at a ‘start’ terminal 701 generallyresponsive to an event (for example, the detection of the potential forestablishing a preferred channel, or in response to a user's action),and continues to a ‘pre-authentication’ procedure 703 (that invokes thepre-authentication process for a prospective member device 500 that hasbeen previously described with respect to FIG. 5). Once the‘pre-authentication’ procedure 703 completes, the prospective memberdevice can communicate over a network. At a ‘request provisioninginformation’ procedure 705, the prospective member device sends arequest for a credential and any other desired and availableprovisioning information. A ‘receive credential’ procedure 707 receivesthe credential and at a ‘receive provisioning information’ procedure 709receives other requested provisioning information that was sent by theautomatic prospective member device credential provisioning process 600.The received credential and possible other provisioning information canthen be made available for use (whether by applications within theprospective member device, by readers of the prospective member device,or by other ways known in the art to use the credential). The‘prospective member device-side provisioning’ process 700 completesthrough an ‘end’ terminal 711.

One skilled in the art will understand that some embodiments provisionan IPSEC VPN instead of (or in addition to) 802.1X and EAP-TLS protocolson a wireless network (or for a wired network). Furthermore, otherembodiments are envisioned that include a firewall and thatautomatically provision credentials to systems/users that allow thesystems/users to communicate through the firewall. This can includeallowing the system to connect over the VPN to the network protected bythe firewall from the internet or wired or wireless LAN. Such a one willunderstand that some embodiments can be used to secure wireless LANsusing techniques such a keyed hopping patterns, etc.

FIG. 8 illustrates a wireless access point secure credentialinfrastructure system 800 that uses a provisioning device 801 that isalso configured as a wireless access point (WAP) for providingelectronic signals through an antenna 803. WAPs are well known in theart and generally conform to 802.11(a), (b), or (g) although they canalso conform to other standards currently in existence or yet to bedeveloped. One skilled in the art will understand how to build a WAP.The provisioning device 801 is one embodiment of a credential issuingdevice and/or a provisioning device.

The provisioning device 801 can have additional functionality such as aswitch, router, DSL or cable modem, firewall, VPN client or terminator,and a credential issuing authority. These capabilities are not shown inFIG. 8. The provisioning device 801 also has one or more ports that canbe used to establish a preferred channel (for example, ports such as aninfrared or visible communication port 805, a microphone 807, a speaker809, an audio output 811, an audio input 813, a USB-A receptacle 815, aUSB B receptacle 819, electrical contacts (not shown), and a near fielddetection area 817). The provisioning device 801 can establish apreferred channel with a prospective member device 821 using one of theports in any number of ways. The preferred channels supported by theprovisioning device 801 can include infrared, audible or inaudible audio(for example, sound and ultrasound), electrical representation of audioor other signals, information sent between the prospective member device821 and the provisioning device 801 through a USB cable attached to theUSB B receptacle 819, via a removable token that can be plugged into theUSB-A receptacle 815 and passed to an appropriately equipped prospectivemember device, or by near field signaling by a human touching the nearfield detection area 817 on the provisioning device 801 while touching adetection area on the prospective member device 821. Furthermore, apreferred channel can include communication established using thetelephone or cell phone switching system using signaling tones over ahandset, or by direct connection to through a telephone jack.

Another possible port can be a camera used to capture an image of acomputer screen that displays information (such as text, dataglyphs, orchanging patterns). Another possible technology for the preferredchannel can be short range radio frequency technology. Furthermore, theinformation can be provided to the prospective member device 821 and theprovisioning device 801 using a keyboard, keypad, touch screen, etc. forhaving a user manually enter the information.

The prospective member device 821 includes an antenna 823, and one ormore ports (not shown) that will enable communication across a preferredchannel (in this case using audio connection cables 825 between theprovisioning device 801) and the prospective member device 821.

The provisioning device 801 can be used to provision wireless networkeddevices by providing SSID codes and WEP keys, to provision wireless orwired network devices by providing network configuration informationsuch as IP addresses, proxy information, domain information etc., toprovision or provide application-specific information, or provision acredential.

For example, a computer, wireless access port (WAP), or otherprovisioning device having a preferred channel and that is configured toperform the ‘secure credential infrastructure construction’ process 200can be used to construct a public key infrastructure.

When the credential issuing device is incorporated within a wirelessaccess point (WAP) one embodiment of the invention can be used toprovision network devices that access the WAP with network configurationinformation. This provisioning can be by adding the network device tothe secure credential infrastructure such that the network device is aprospective member device. In addition, the credential issuing devicecan provide a key recognized by the WAP (for example a SSID and a keyfor used by a Wired Equivalent Privacy (WEP) capability in the WAP) tothe network device over the preferred channel thus automating theerror-prone and confusing entry of a long string of charactersrepresenting the key as is required by the current technology (some WAPsallow the use of a passphrase instead of directly providing the actualkey, but the use of the passphrase reduces the WEP security—in addition,consider the difficulties of someone who is dyslexic when entering longarbitrary strings of characters)—further consider the consequence ofnaive users not understanding that the key is in hex base thus reducingthe number of potential key combinations by limiting the text of the keyto numeric characters.

One skilled in the art will understand that shared secrets as well asWEP keys can be provisioned (for example, any key shared by theinfrastructure and one or more member devices). In particular, any“network password”, or any type of symmetric key meant to eitherdirectly encrypt data for the wireless network, to authenticate a deviceto the wireless network, information required to establish a VPN on awired or wireless network, and/or protect further key exchange.

Where the provisioning device 801 serves as a router, modem, or WAP, theprovisioning device 801 can monitor the traffic passing through theprovisioning device 801 to determine whether the traffic is from amember device (that is, a device that is authorized to use a securechannel) or from some other unauthorized device. Where the provisioningdevice 801 determines that the device is a member, packets sourced fromthe member device can be automatically routed through the secure channelwhile packets sourced from an unauthorized device are routed through anopen channel.

One skilled in the art will understand how to apply these techniques torouters, bridges, hubs, firewalls, VPNs, and devices other than a WAP.

FIG. 9 illustrates an enrollment station based configuration 900 thatallows a credential issuing device 901 (or certification authority) toaccess multiple enrollment stations (each having a location-limitedchannel) at different locations. This allows the location-limitedchannels to be deployed at multiple locations (such as at each remoteoffice of a company). By deploying the enrollment stations at multiplelocations, those who want to enroll a device in the secure credentialinfrastructure can do so simply by traveling to one of the enrollmentstations. The use of the enrollment station can be one way to include ahuman in the certification process (such as a registration agent orother agent) to add additional information and authorize the enrollmentof the prospective member device with the secure credentialinfrastructure. Another advantage of the use of the enrollment stationis that it allows the credential issuing device 901 (providing thecredential issuing authority service) to use off-the-shelf software thathas no knowledge of pre-authentication or of the preferred channel.

A registration agent or other agent can also limit addition ofprospective member devices (beyond the requirement that the prospectivemember device have access to the preferred channel as has been describedthroughout) by, for example but without limitation, using a specialtoken (USB device, biometric sensor, etc.) to approve thepreauthorization; using another device to approve the addition (forexample, a requirement that the owner of the secure credentialinfrastructure (or authenticated user of the enrollment station) can benotified (and may need to provide approval) when a prospective memberdevice is being pre-authenticated.

The credential issuing device 901 can communicate over a network 903 toa member device 905 over a network connection 907. In addition, thecredential issuing device 901 can communicate to an enrollment station909 over a secure network connection 911 (such as a VPN). The enrollmentstation 909 can enroll the member device 905 over a preferred channel913 and communicate with the credential issuing device 901 over thesecure network connection 911. The credential issuing device 901 and theenrollment station 909 can mutually authenticate each other usingtechniques known in the art as well as techniques described herein.

As was previously described, there exists a problem with simplifying theconfiguration of network devices. This problem can be addressed byanother embodiment of the invention that is a network provisioningdevice. The network provisioning device has a preferred channel that canbe used to provide a network device with network configurationinformation to enable the network device to communicate. Much of thedetail of this function has been previously described.

FIG. 10 illustrates an automatic network device configuration process1000 that can be used by the network provisioning device. The automaticnetwork device configuration process 1000 initiates at a ‘start’terminal 1001 at power on or reset and continues to a ‘configureprovisioning device’ procedure 1003 that initializes the networkprovisioning device and allows a user or initialization system tospecify the required network information. An ‘establish communicationwith network device over a preferred channel’ procedure 1005 establishescommunication with the network device over a preferred channel in asimilar manner as has been described (although in some embodiments withsignificantly less security). Once communication is achieved, a ‘sendnetwork configuration information to network device’ procedure 1007sends the network configuration information to the network device. Oneskilled in that art will understand that a credential can also beprovided if so desired as was previously described.

As was previously described, there exists a problem in the medicalenvironment where cabled sensors are difficult to work around, but it iscurrently too difficult to provision wireless sensors to be sufficientlysecure to protect the patient's privacy. However, having the capabilityto simply issue and administer credentials, as has been previouslydiscussed, now enables a new solution to this problem.

Another embodiment of the invention can be applied to informationmanagement and distribution in environments where the data gathered bywireless sensors and where the data is private or legally protected. Oneexample of such an environment is a hospital. Instead of the currentlabor intensive and cumbersome method of taking a patient's vitalmeasurements—that is by requiring a human to take and record themeasurements, using automated sensors to capture the patient's data andsecurely transmitting that data to a database or other repository.However, having wires attached to these sensors greatly adds to thehospital room clutter, and often annoy the patient, doctors, nurses andother hospital staff. Thus, wireless sensors would be desired. However,before this approach will succeed, the wireless sensors must be simpleto setup and to secure such that no unauthorized individuals can accessthe patient data measured by the sensor.

As new devices (for example, sensors, data stations, etc.) are acquiredby the hospital or medical practice, they can be configured at anenrollment station with a credential provided by a credential issuingauthority as part of the hospital or practice security infrastructure.In addition, other configuration information (possibly entered by anoperator) can be provided to the device to enable that device to operatein its usage environment (this information can include a commitment tothe data server that the new device is to access, thus allowing thedevice to know that it is communicating with a legitimate datarepository and preventing the use of rogue devices designed to gatherpatient data in an unauthorized fashion).

A particular sensor can then be associated (temporarily) with aparticular patient by using a similar pre-authentication exchange with abedside enrollment station associated with that patient, or with aconfiguration interface at a nurse's station or doctor's desk, whichsimply stores information about the public key of that device in thelist of authorized devices for that patient. Communication between thesensor and the back-end hospital infrastructure, or remote datacollection site is then secured using standard techniques (for example,IPsec, SSL), and data is associated with the appropriate patient by acombination of information provided by the device (that it received atconfiguration time), and the system's record of the devices associatedwith a particular patient.

In the case of remote monitoring, the hospital or practice firewall canbe configured to allow incoming data connections from any of the deviceswith hospital/practice credentials (part of the instant PKI), along thelines of a self-configuring VPN.

FIG. 11 illustrates a secure wireless sensor system 1100 showing the useof wireless sensors in the home and hospital settings. A patient isassociated with a sensor 1101 that has been provisioned with acredential (as well as other data) as described above and provided withpatent identification. The sensor 1101 gathers information related tothe patient and securely sends that information to a patient datastorage 1107 through the wireless access point 1103 over the wirelesscommunication channel 1105 (for example, by establishing a securecommunication channel using the provisioned credential). The sensors cansecurely communicate to any WAP in the medical facility as the patientmoves thus maintaining continuous ability for the sensors to transmitinformation to the patient data storage 1107. Further, because wirelesssensors are enabled by some embodiments, additional sensors can beusefully attached to the patient. One such example is a sensor thatrecognizes the location of the patient such that the hospitaladministration can constantly know where a mobile patient is at anytime. Such a sensor allows hospital staff to respond more quickly ifother sensors indicate a problem with the patient (as well as being ableto detect where a patient is when it time to administer medication).Other techniques can be used to track a patient by using triangulationmethods based on the strength of wireless reception of multiple WAPs.

In addition, a nurse or other medical professional who has anappropriate credential can provision the sensor with patient specificinformation such as Patient identification, alarm limits, dosageschedules etc.

Sensors on a remote patient such as a remote sensor 1109 securelycommunicate to a wireless access point 1111 over a wirelesscommunication channel 1113. The wireless access point 1111 sends theinformation through a network 1115 and a hospital firewall 1117 to thepatient data storage 1107. The remote sensor 1109 can be provisioned atthe hospital, at an enrollment station at the office of the patient'sdoctor, or otherwise. This approach to medical monitoring removessignificant clutter in the patient's room, while still providing securecommunication of the patient data.

One skilled in the art will understand that the wireless access point1103 and the wireless access point 1111 can also be used as anenrollment station in communication with a credential issuing device atthe hospital, can be used as a credential issuing device, and can alsobe used to provision the sensors with specific patient related data,such as patient data, limit data, alarm data, dosage data, intervaldata, access data, physician data, caregiver data, nurse data, insurancedata and room assignment data.

One skilled in the art will understand that some embodiments can beapplied to any sensor. In particular, some embodiments can be applied toelements of sensor networks for surveillance, home or office security,or other devices that need to be secure (including location andproximity sensors). Furthermore, the sensor can sense and/or measuremedical information, location information, proximity information,environmental information (such as exposure to particle radiation,chemical vapors, sound levels, smoke levels, environmental heat,altitude, wind speed, vibration, proximity to motion, humidity, andbiological agents), as well as sensors within a vehicle or group ofvehicles (such as vehicle speed, vehicle orientation, status of vehiclesub-components (such as airfoils, engine or motor measurements, brakes,etc.), or robots). Further sensors can be used to recognize images oflocations, objects, people, and targets as well as recognizingcharacteristic noises. Such sensors can also have activation componentsthat are controlled by data within the provisioning information (such asdosage data, interval data, activation data, etc.).

Another problem that solved by some embodiments is that of providingsecure communications between an emergency operation center (EOC) andthe residents at potential risk from an emergency. As previouslydescribed, there exists a problem with current means for providingcitizens with emergency warnings. These problems include the difficultyof reaching only a portion of the citizen base, and the difficulty inmaking sure that the warning system is secure such that unsavorycharacters cannot use the system to annoy or harass citizens.

Having the capability to simply issue and administer credentials, as hasbeen previously discussed, now allows a new solution to this problem.

FIG. 12 illustrates one embodiment of a secure community alert system1200. Each person covered by the secure community alert system 1200receives a resident alert device 1201 (or other situation notificationdevice) for insertion in the resident's domicile. The resident alertdevice 1201 includes a display portion 1203 that serves as a means ofproviding information to those in the domicile. It also includes anaudible speaker 1205 for alerting those in the domicile and a warninglight/disable switch 1207 for providing a visual alert, a means forsilencing the audible speaker 1205, and means to respond to messagesdisplayed on the display portion 1203. The resident alert device 1201also includes an enrollment port 1209 that can enable a preferredchannel as previously described (however, the enrollment port 1209 canalso be a telephone or Ethernet jack such that the resident alert device1201 can be provisioned from a known telephone number or internetaddress). The resident alert device 1201 can receive alarm information(or general subject matter information) from a transmission mechanism1211 such as by an emergency radio or television station or otherwireless means (for example by use of the cellular phone system), by useof the wired telephone system, by use of the Internet, or any other datacommunication mechanism.

Some of the embodiments of the resident alert device 1201 can haveadditional options for the hearing or visually impaired, those whocannot read, etc.

The resident alert device 1201 can be provisioned by an enrollmentstation 1213. Provisioning can be accomplished at the time the residentalert device 1201 is provided to the resident, by providing the deviceun-provisioned such that the resident provisions the device at home byconnecting the device to the telephone network. People without securityexpertise can now provision the resident alert device 1201 becauseprovisioning is now a simple procedure.

Another aspect that can be provided by some embodiments of the residentalert device 1201 is that of a forwarding service. That is, once thealert is received by the resident alert device 1201, the alert can beforwarded to an e-mail address, text messaging system, or voicetelephone number.

The functions of the resident alert device 1201 can be incorporated intoother home and office electronic devices such as a computer, atelevision, a radio, a telephone, a push to talk device, a pager, aclock, a thermostat, a network appliance, or a home appliance.

During an emergency it is critical that the EOC can communicate withthat device in a way that provides certain guarantees.

For the citizen it is necessary to know that the communication is agenuine alert from the EOC and not, say, some criminal who is attemptingto get the home owners to leave their house in a hurry and potentiallyleave the house vulnerable to theft.

For the EOC it is important to be able to specify the devices and becertain that they are communicating with the intended devices and onlythe intended devices. This requirement would be necessary in a floodemergency for example, where evacuation instructions would need to beissued to people in stages of danger and direct them to differentplaces, via different routes to avoid congestion en route and at theevacuation sites.

One skilled in the art will understand that the network transmitsinformation (such as the previously described data as well as data thatdefines a computer program). Generally, the information is embodiedwithin a carrier-wave. The term “carrier-wave” includes electromagneticsignals, visible or invisible light pulses, signals on a data bus, orsignals transmitted over any wire, wireless, or optical fiber technologythat allows information to be transmitted over a network. Programs anddata are commonly read from both tangible physical media (such as acompact, floppy, or magnetic disk) and from a network. Thus, thenetwork, like a tangible physical media, is a computer usable datacarrier.

In addition, the flowcharts provided herein are for illustrativepurposes and are used to teach one embodiment of the invention. Otherflowcharts that incorporate the underlying ideas (or modificationsthereof) are to be considered as equivalent.

One skilled in the art will understand that embodiments of the inventionvastly simplify the creation, management, and maintenance of securecredential infrastructure. Thus, a PKI can be cheaply and efficientlycreated and administered. Furthermore, the characteristics of someembodiments now enable the use of secure credential infrastructure inapplications and environments where the expense and overhead related totraditional secure credential infrastructure were prohibitive.

From the foregoing, it will be appreciated that embodiments of theinvention have (without limitation) one or more of the followingadvantages:

-   -   1) ability to quickly and simply create, maintain, and manage        secure credential infrastructure by non-security exports;    -   2) dramatically improved security available to the public        because of the decrease in cost and effort in creating a secure        credential infrastructure now enables the computer layperson to        keep their communications secure;    -   3) enables the use of wireless sensors that provide sensitive        personal data about the person without fear of the information        be intercepted or of violating privacy statutes;    -   4) enables the use of alarm systems (such as neighborhood alert        systems) that are completely secure from being misused by        somebody outside of the alarm system;    -   5) enables simple setup of secure wireless access points;    -   6) enables simple provisioning of network devices (either with        credentials, with network-specific information,        application-specific information, or combination of these; and    -   7) enables the ability to join a PKI without requiring onerous        trust verification processes.

While particular embodiments have been described, alternatives,modifications, variations, improvements, and substantial equivalentsthat are or may be presently unforeseen may arise to applicants orothers skilled in the art. Accordingly, the appended claims as filed andas they may be amended are intended to embrace all such alternatives,modifications variations, improvements, and substantial equivalents.

1. A method for facilitating secure communication between two networkeddevices, comprising: establishing communication between a situationnotification device and a provisioning device over a preferred channel,wherein the preferred channel is bidirectional, location-limited, has ademonstrative identification property and an authenticity property, anddoes not require being resistant to eavesdropping; wherein thedemonstrative identification property allows a human operator to beaware of which devices are communicating with each other based onphysical proximity; and wherein the authenticity property makes itdifficult or impossible for attacking devices to tamper with or altermessages transmitted in the preferred channel, or to insert falseinformation into the preferred channel without being detected bylegitimate participants communicating via the preferred channel; priorto establishing the communication, pre-authenticating the situationnotification device to ensure that the situation notification device hasphysical access to the preferred channel, wherein pre-authenticating thesituation notification device involves: exchanging key commitmentinformation between the provisioning device and the situationnotification device over the bidirectional preferred channel; exchangingkeys between the provisioning device and the situation notificationdevice over a bidirectional channel which does not have to be thepreferred channel; and verifying the received keys using the receivedkey commitment information on both the provisioning device and thesituation notification device; providing provisioning information tosaid situation notification device over said preferred channel, whereinsaid situation notification device is automatically configured toreceive subject matter information responsive to said provisioninginformation; receiving said subject matter information; verifying saidsubject matter information with said provisioning information; andpresenting said subject matter information to a user of the situationnotification device responsive to the step of verifying, wherein thestep of verifying ensures that the subject matter information isgenuine.
 2. The method of claim 1, wherein the step of providing furthercomprises: exchanging key commitment information over said preferredchannel between said provisioning device and said situation notificationdevice; receiving a public key by said situation notification device;verifying said public key with said key commitment information; andreceiving a credential authorized by a credential issuing authority. 3.The method of claim 1, wherein said preferred channel is alocation-limited channel.
 4. The method of claim 1, wherein saidpreferred channel uses a telephone switching system.
 5. The method ofclaim 1, wherein subject matter information is received using anantenna, a telephone line, a local area network, a wide area network, awireless network, or a broadcast network.
 6. The method of claim 1,wherein said situation notification device is a computer, a television,a radio, a telephone, a push to talk device, a pager, a clock, athermostat, a network appliance, or a home appliance.
 7. The method ofclaim 1, further comprising forwarding said subject matter information.8. The method of claim 1, wherein said subject matter information isalarm information.
 9. A computer-readable storage medium storinginstructions that when executed by a computer cause the computer topresent subject matter information, the method comprising steps of:establishing communication between a situation notification device and aprovisioning device over a preferred channel, wherein the preferredchannel is bidirectional, location-limited, has a demonstrativeidentification property and an authenticity property, and does notrequire being resistant to eavesdropping; wherein the demonstrativeidentification property allows a human operator to be aware of whichdevices are communicating with each other based on physical proximity;and wherein the authenticity property makes it difficult or impossiblefor attacking devices to tamper with or alter messages transmitted inthe preferred channel, or to insert false information into the preferredchannel without being detected by legitimate participants communicatingvia the preferred channel; prior to establishing the communication,pre-authenticating the situation notification device to ensure that thesituation notification device has physical access to the preferredchannel, wherein pre-authenticating the situation notification deviceinvolves: exchanging key commitment information between the provisioningdevice and the situation notification device over the bidirectionalpreferred channel; exchanging keys between the provisioning device andthe situation notification device over a bidirectional channel whichdoes not have to be the preferred channel; and verifying the receivedkeys using the received key commitment information on both theprovisioning device and the situation notification device; providingprovisioning information to said situation notification device over saidpreferred channel, wherein said situation notification device isautomatically configured to receive said subject matter informationresponsive to said provisioning information; receiving said subjectmatter information; verifying said subject matter information with saidprovisioning information; and presenting said subject matter informationto a user of the situation notification device responsive to the step ofverifying, wherein the step of verifying ensures that the subject matterinformation is genuine.
 10. The computer-readable storage medium ofclaim 9, wherein the step of providing further comprises: exchanging keycommitment information over said preferred channel between saidprovisioning device and said situation notification device; receiving apublic key by said situation notification device; verifying said publickey with said key commitment information; and receiving a credentialauthorized by a credential issuing authority.
 11. The computer-readablestorage medium of claim 9, wherein said preferred channel is alocation-limited channel.
 12. The computer-readable storage medium ofclaim 9, wherein said preferred channel uses a telephone switchingsystem.
 13. The computer-readable storage medium of claim 9, whereinsubject matter information is received using an antenna, a telephoneline, a local area network, a wide area network, a wireless network, ora broadcast network.
 14. The computer-readable storage medium of claim9, wherein said situation notification device is a computer, atelevision, a radio, a telephone, a push to talk device, a pager, aclock, a thermostat, a network appliance, or a home appliance.
 15. Thecomputer-readable storage medium of claim 9, further comprisingforwarding said subject matter information.
 16. The computer-readablestorage medium of claim 9, wherein said subject matter information isalarm information.
 17. An apparatus comprising: at least one portconfigured to establish a preferred channel, wherein the preferredchannel is bidirectional, location-limited, has a demonstrativeidentification property and an authenticity property, and does notrequire being resistant to eavesdropping; wherein the demonstrativeidentification property allows a human operator to be aware of whichdevices are communicating with each other based on physical proximity;and wherein the authenticity property makes it difficult or impossiblefor attacking devices to tamper with or alter messages transmitted inthe preferred channel, or to insert false information into the preferredchannel without being detected by legitimate participants communicatingvia the preferred channel; a first communication mechanism configured toreceive provisioning information over said preferred channel, wherebythe apparatus is configured to be able to receive subject matterinformation responsive to said provisioning information, wherein theport is further configured to pre-authenticate the first communicationmechanism prior to receiving the provisioning information to ensure thatthe first communication mechanism has physical access to the preferredchannel, wherein pre-authenticating the situation notification deviceinvolves: exchanging key commitment information between the provisioningdevice and the situation notification device over the bidirectionalpreferred channel; exchanging keys between the provisioning device andthe situation notification device over a bidirectional channel whichdoes not have to be the preferred channel; and verifying the receivedkeys using the received key commitment information on both theprovisioning device and the situation notification device; a secondcommunication mechanism configured to receive said subject matterinformation subsequent to operation of the first communicationmechanism; a verification mechanism configured to verify said subjectmailer information with said provisioning information; and apresentation mechanism configured to present said subject matterinformation to a user of the situation notification device responsive tothe verification mechanism, wherein the step of verifying ensures thatthe subject matter information is genuine.
 18. The apparatus of claim17, wherein the first communication mechanism further comprises: a keycommitment receiver mechanism configured to receive key commitmentinformation through said at least one port; a key receiver mechanismconfigured to receive a public key; a pre-authentication mechanismconfigured to verify said public key with said key commitmentinformation; and a credential provisioning mechanism configured to beable to automatically provide a credential authorized by a credentialissuing authority responsive to the pre-authentication mechanism. 19.The apparatus of claim 17, wherein said preferred channel is alocation-limited channel.
 20. The apparatus of claim 17, wherein saidpreferred channel uses a telephone switching system.
 21. The apparatusof claim 17, wherein subject matter information is received using anantenna, a telephone line, a local area network, a wide area network, awireless network, or a broadcast network.
 22. The apparatus of claim 17,wherein the apparatus is within a computer, a television, a radio, atelephone, a push to talk device, a pager, a clock, a thermostat, anetwork appliance, or a home appliance.
 23. The apparatus of claim 17,further comprising a forwarding mechanism configured to forward saidsubject matter information.
 24. The apparatus of claim 17, wherein saidsubject matter information is alarm information.
 25. The method of claim1, wherein said preferred channel has a demonstrative identificationproperty and an authenticity property.
 26. The computer-readable storagemedium of claim 9, wherein said preferred channel has a demonstrativeidentification property and an authenticity property.
 27. The apparatusof claim 17, wherein said preferred channel has a demonstrativeidentification property and an authenticity property.